Sources Of Information
1. Fay, John. 1987. The Helicopter History, Piloting and How it Flies. New York: Hippocrene Books.
2. Gunstun, Bill; Spick, Mike. 1986. Modern Fighting Helicopters. New York: Crescent Books.
3.Ireland Karin. 1983. Helicopters at Work. New York: Julian Messner.
13. www.zap16.com
14.Young, Warren, R. 1982. The Helicopters. Alexandria: Time-Life Books.